Implantable controlled release devices for drug delivery have been developed. Certain devices rely upon the gradual release of a drug from a polymeric carrier over time, due to degradation of the carrier. Polymer-based drug release devices are being developed that include a drug in a ferropolymer that may be heated by an externally applied magnetic field, thus influencing the drug release. MEMS based drug release devices that include integrated electrical circuitry are also under development, as are MEMS based systems for performing chemical reactions. Implantable osmotic pump devices have been developed for drug delivery purposes. Wireless transmission of electromagnetic signals of various frequencies is well known in the areas of communications and data transmission, as well as in selected biomedical applications.